As this round of the IPCC unfolds, developing countries are scurrying to relieve themselves of any major responsibility for historic emissions and, consequently, aggressive mitigation policies.

For example, China has requested inserting language that formally recognizes the percentage of emissions for which developed countries are responsible — 95 percent from the pre-industrial era until 1950, and 77 percent from 1950 to the start of the millennium.

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China is also trying to earn reduction credit for social policies that have unintentionally curbed emissions — in other words, the one-child policy. Elsewhere, efforts to reduce air pollution from factories and cars has slowed emissions growth.

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And yet China is poised to pass the U.S. in annual emissions this year or next, so it will need to join emissions-reductions efforts soon after we do, whenever that will be …

This post was created for, a project of the Center for American Progress Action Fund.